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Gut Health

Dietary Treatment for IBS

Dietary Treatment for IBS
Kaitlin Colucci
Writer and expert1 day ago
View Kaitlin Colucci's profile

IBS (Irritable Bowel Syndrome) is a so-called functional gastrointestinal disorder that affects 15-20% of the world's population. Common symptoms include bloating, gas, abdominal pain, and diarrhea or constipation. Currently, there is no medical treatment that alleviates all IBS symptoms. The treatment with the best evidence and used worldwide is the low FODMAP diet. This treatment focuses on reducing fermentable carbohydrates known to cause IBS symptoms. 

What is FODMAP? 

The low FODMAP diet originates from Monash University in Australia, where research began around 2005. Many studies have been conducted since then, almost all showing that a low FODMAP diet reduces symptoms in about 75% of people with IBS. 

FODMAPs (Fermentable Oligo-, Di-, Monosaccharides and Polyols) are a group of short-chain carbohydrates and sugar alcohols that are not fully absorbed in the small intestine. They include: 

  • Oligosaccharides: Found in foods like wheat, onions, and garlic. 
  • Disaccharides: Lactose in dairy products from cows, goats, and sheep. 
  • Monosaccharides: Fructose found in fruits such as apples and pears. 
  • Polyols: Found in certain fruits and artificial sweeteners like xylitol and sorbitol. 

The low FODMAP diet consists of three phases: elimination, reintroduction, and personalisation. During the elimination phase, high-FODMAP foods are removed from the diet, then gradually reintroduced to identify which specific FODMAPs cause symptoms. Typically, between 10-15 foods are identified to avoid for lasting symptom relief. As the low FODMAP diet is a disease-specific diet treatment (i.e. recommended only for individuals diagnosed with IBS or other complex gut disorders), only trained dietitians should provide such guidance to patients. With long-term support and follow-up, the chances of understanding which foods to avoid and which are tolerated increase, making the diet more varied and easier to manage daily. 

Bifidobacteria and Gut Health 

Bifidobacteria are a group of beneficial bacteria primarily found in the large intestine and play a significant role in promoting gut health and digestion. They contribute in several ways: 

  • Aid Digestion: Bifidobacteria help break down complex carbohydrates like FODMAPs, facilitating nutrient absorption and reducing symptoms. 
  • Strengthen the Immune System: These bacteria interact with the immune system and enhance protection against harmful bacteria. 
  • Improve Gut Barrier Function: Bifidobacteria reduce the permeability of the intestinal wall, preventing harmful substances from entering the bloodstream. 
  • Produce Short-Chain Fatty Acids (SCFAs): They ferment dietary fibers to produce SCFAs, such as butyrate, which have anti-inflammatory properties and provide energy to intestinal cells. 

Studies have shown that people with IBS often have an imbalance in their gut flora, including lower levels of bifidobacteria. This reduction can contribute to IBS symptoms by impairing the breakdown of FODMAPs, decreasing SCFA production, and weakening the gut barrier function. 

Impact of the Low FODMAP Diet on Bifidobacteria 

A challenge with the low FODMAP diet is that the intake of prebiotic fibres, which feed gut bacteria, often decreases during the elimination phase. This is because the intake of foods like onions, garlic, and grains is reduced, which can negatively affect the gut flora in the long term. Several studies have shown that individuals following the low FODMAP diet experienced a reduction in bifidobacteria in the gut. 

There are several ways to mitigate the diet's impact on gut flora while ensuring nutritional intake: 

  • Reintroduction: After the elimination phase, FODMAP groups should be gradually reintroduced to identify which are better tolerated and to contribute to a more varied diet. 
  • Probiotic Supplements: Using probiotic supplements containing bifidobacteria can help restore levels of these beneficial bacteria. 
  • Prebiotic Foods: There are many low-FODMAP foods that act as prebiotics, such as oats, vegetables, fruits, berries, nuts, seeds, and certain legumes. These feed the bifidobacteria without causing IBS symptoms. 

Bifidobacterium Longum 35624™ 

Bifidobacterium longum 35624™ is a unique bacterial strain that has been extensively studied for its health benefits, particularly in connection with IBS and the low FODMAP diet. It is used to increase the proportion of bifidobacteria and can help prevent their unwanted reduction during the elimination phase. 

"We have worked with Bifidobacterium Longum 35624™ as a supplement during the elimination phase for many years. Many patients with IBS experience positive effects and can gradually tolerate more high-FODMAP foods that they previously reacted to.” says Kaitlin Colucci, registered dietitian at Belly Balance. 


Digital IBS treatment 

Belly Balance offers a digital IBS treatment in their app Belly Balance. The app is just being launched into the UK market and is free to download for everyone. The app consists of a 11 step IBS treatment, recipes, FODMAP lists and a FODMAP barcode scanner, everything to help the user in everyday life. The app has over 120 000 downloads in Sweden where it originate from, and is validated to help over 85% of the users with their IBS symptoms. Belly Balance work together with dietitians and gastro doctors to increase awareness of IBS and make IBS treatment accessible for everyone. Download the app here.     


Kaitlin Colucci
Writer and expert
View Kaitlin Colucci's profile
Kaitlin Colucci Registered Dietitian